Battery drain issues!

[TheWanderer]

Hey everyone!
Been a while since I posted last but I am happy to say after having the transmission replaced on my motorhome she has been running well for me and I am back on the road!
I have ran into a bit of an issue recently though with my house battery I am hoping y'all can help me investigate.
Generally the battery seems to behave as it should. Takes a charge fine while driving or running my generator, and charges to 2.6-2.8v. Generally I can charge my phone on that, run lights, a small 12v fan overnight, and thats about it before recharging the next day around 12-12.2v.
I am not currently using my fridge nor furnace so they should not be causing much or any draw.
There has been a couple mornings however where I have woken up to a terrible voltage reading of only about 10v! ??
It happened a week ago or so and I was worried my battery might be bad, but after charging it that time it seemed to work correctly for a week without overdischarging until last night. Woke up this morning and another 10v reading. Double-checked at the battery with voltmeter and confirmed at 10.5v.
What could be causing such a drastic difference or drain randomly like that?
My suspisions are either bad battery (i sure hope not), bad ground possibly, or some other drain/connection issue.
Thanks in advance for any advice you can give. 🙂

[rk911]

hydrometers are inexpensive. pick one up for your tool box at the hardware store when you take your battery in to be load tested. but don't ignore the importance of clean and corrosion free battery terminals and cable ends. i'd still check and clean them as needed. good luck.

[TheWanderer]

Well I do not own a hygrometer currently but I am planning on taking the battery in to have it tested whenever I leave camp. I can get by a couple more days out here with or without the house battery's help. Haha but yeah I am kind of leaning towards the bad battery as being the culprit. Just with how heavily drained the battery has gotten (10 volts only), I doubt I have any drain on the battery that intense I wouldn't know about.

[rk911]

i’ve always believed in doing simple things first. if it were me and assuming you have the typical lead acid batteries...

- charge your batteries as you usually do then disconnect the cables and let them rest (zero draw) for about 20-mins. then check each cell with a hydrometer to see the actual state of charge.

- before reconnecting clean the battery posts and cable ends till they shine before reconnecting